Answer:
Approximately [tex]4.75[/tex].
Step-by-step explanation:
Remark: this approach make use of the fact that in the original solution, the concentration of [tex]\rm CH_3COOH[/tex] and [tex]\rm CH_3COO^{-}[/tex] are equal.
[tex]{\rm CH_3COOH} \rightleftharpoons {\rm CH_3COO^{-}} + {\rm H^{+}}[/tex]
Since [tex]\rm CH_3COONa[/tex] is a salt soluble in water. Once in water, it would readily ionize to give [tex]\rm CH_3COO^{-}[/tex] and [tex]\rm Na^{+}[/tex] ions.
Assume that the [tex]\rm CH_3COOH[/tex] and [tex]\rm CH_3COO^{-}[/tex] ions in this solution did not disintegrate at all. The solution would contain:
[tex]0.3\; \rm L \times 0.2\; \rm mol \cdot L^{-1} = 0.06\; \rm mol[/tex] of [tex]\rm CH_3COOH[/tex], and
[tex]0.06\; \rm mol[/tex] of [tex]\rm CH_3COO^{-}[/tex] from [tex]0.2\; \rm L \times 0.3\; \rm mol \cdot L^{-1} = 0.06\; \rm mol[/tex] of [tex]\rm CH_3COONa[/tex].
Accordingly, the concentration of [tex]\rm CH_3COOH[/tex] and [tex]\rm CH_3COO^{-}[/tex] would be:
[tex]\begin{aligned} & c({\rm CH_3COOH}) \\ &= \frac{n({\rm CH_3COOH})}{V} \\ &= \frac{0.06\; \rm mol}{0.5\; \rm L} = 0.12\; \rm mol \cdot L^{-1} \end{aligned}[/tex].
[tex]\begin{aligned} & c({\rm CH_3COO^{-}}) \\ &= \frac{n({\rm CH_3COO^{-}})}{V} \\ &= \frac{0.06\; \rm mol}{0.5\; \rm L} = 0.12\; \rm mol \cdot L^{-1} \end{aligned}[/tex].
In other words, in this buffer solution, the initial concentration of the weak acid [tex]\rm CH_3COOH[/tex] is the same as that of its conjugate base, [tex]\rm CH_3COO^{-}[/tex].
Hence, once in equilibrium, the [tex]\rm pH[/tex] of this buffer solution would be the same as the [tex]{\rm pK}_{a}[/tex] of [tex]\rm CH_3COOH[/tex].
Calculate the [tex]{\rm pK}_{a}[/tex] of [tex]\rm CH_3COOH[/tex] from its [tex]{\rm K}_{a}[/tex]:
[tex]\begin{aligned} & {\rm pH}(\text{solution}) \\ &= {\rm pK}_{a} \\ &= -\log_{10}({\rm K}_{a}) \\ &= -\log_{10} (1.76 \times 10^{-5}) \\ &\approx 4.75\end{aligned}[/tex].
Brian, the gorilla, was planning a party for his zoo friends. He sent his elves Jamie and Nancy into the North Pole exhibit to count the penguins and reindeer. Jamie said there were 40 legs and Nancy said there were 14 heads. How many penguins and reindeer were in the exhibit?
Answer:
There are 8 penguins and 6 reindeers.
Step-by-step explanation:
Since Brian, the gorilla, was planning a party for his zoo friends, and he sent his elves Jamie and Nancy into the North Pole exhibit to count the penguins and reindeer, and Jamie said there were 40 legs and Nancy said there were 14 heads To determine how many penguins and reindeer were in the exhibit, the following calculation must be performed:
Penguins: 1 head and 2 legs
Reindeers: 1 head and 4 legs
40 - (14 x 2) = X
40 - 28 = X
12 = X
12/2 = 6
14 - 6 = 8
8 x 2 + 6 x 4 = X
16 + 24 = X
40 = X
Therefore, there are 8 penguins and 6 reindeers.
You have to find the value of k
Answer:
115
Step-by-step explanation:
What is the volume of the triangular prism shown below?
10
A. 100 cu. units
B. 200 cu. units
C. 400 cu. units
D. 300 cu. units
Answer:
B. 200 cu. units
Step-by-step explanation:
Volume of the triangular prism = ½*b*h*l
Where,
b = 8 units
h = 5 units
l = 10 units
Plug in the values
Volume of the prism = ½*8*5*10
= 4*5*10
= 200 cu. units
5/6 ÷ 1/3 - 2/3 (2/5)
Answer:
[tex] \frac{67}{30} \: \text{or} \:2 \frac{7}{30} [/tex]
Step-by-step explanation:
5/6 ÷ 1/3 - 2/3 (2/5)
= 5/6 ÷ 1/3 - 2/3 × 2/5= 5/2 - 2/3 × 2/5= 5/2 - 4/15= 67/30 or 2 7/30Hope it helps you! ＼(^ᴥ^)／
A certain list of movies were chosen from lists of recent Academy Award Best Picture winners, highest grossing movies, series movies (e.g. the Harry Potter series, the Spiderman series), and from the Sundance Film Festival and are being analyzed. The mean box office gross was $138.64 million with a standard deviation of $11.2526 million. Given this information, 98.49% of movies grossed greater than how much money (in millions)
Can someone help asap?
Answers:
sin = -5/13tan = 5/12csc = -13/5sec = -13/12cot = 12/5=============================================
Explanation:
The angle theta is between pi and 3pi/2, excluding both endpoints.
This places theta in the third quadrant (Q3) between 180 degrees and 270 degrees. The third quadrant is in the southwest.
Plot point A at the origin. 12 units to the left of this point, will be point B. So B is at (-12,0). Then five units lower is point C at (-12,-5). Refer to the diagram below. Notice how triangle ABC is a right triangle.
The angle theta will be the angle BAC, or simply angle A.
Since cos(theta) = -12/13, this indicates that
AB = -12 = adjacent
AC = 13 = hypotenuse
Technically, AB is should be positive, but I'm making it negative so that we can then say
cos(angle) = adjacent/hypotenuse
cos(theta) = AB/AC
cos(theta) = -12/13
------------------
If you apply the pythagorean theorem, you should find that BC = 5, which I'll make negative since we're below the x axis. Then we can say
sin(theta) = opposite/hypotenuse
sin(theta) = BC/AC
sin(theta) = -5/13
------------------
If you divide sine over cosine, then you'll get 5/12. The 13's cancel out. This is the value of tangent.
Or you could say
tan(theta) = opposite/adjacent
tan(theta) = BC/AB
tan(theta) = (-5)/(-12)
tan(theta) = 5/12
------------------
To find csc, aka cosecant, you apply the reciprocal to sine
sin = -5/13 which means csc = -13/5
sec, or secant, is the reciprocal of cosine
cos = -12/13 leads to sec = -13/12
and finally cotangent (cot) is the reciprocal of tangent
tan = 5/12 leads to cot = 12/5
------------------
Note: everything but tan and cot is negative in Q3.
How would I draw the reflection over the line y=2x+5?
Answer:
Step-by-step explanation:
I WILL MARK THE ANSWER AS BRAINLIEST BE CORRECT BEFORE YOU ANSWER PLEASE
LOOK AT THE PROBLEM
Answer:
yes I look this problem in this figure
Solve by using matrices. 2x – y +2 + w = -3 x + 2y – 3z + w = 12 3x - y - + 2w = 3 -2x + 3y + 2 – 3w = -3
Some symbols and numbers are missing. I assume the system is supposed to read
2x - y + 2z + w = -3
x + 2y - 3z + w = 12
3x - y - z + 2w = 3
-2x + 3y + 2z - 3w = -3
In matrix form, this is
[tex]\begin{bmatrix}2&-1&2&1\\1&2&-3&1\\3&-1&-1&2\\-2&3&2&-3\end{bmatrix}\begin{bmatrix}x\\y\\z\\w\end{bmatrix}=\begin{bmatrix}-3\\12\\3\-3\end{bmatrix}[/tex]
which we can strip down to the augmented matrix,
[tex]\left[\begin{array}{cccc|c}2&-1&2&1&-3\\1&2&-3&1&12\\3&-1&-1&2&3\\-2&3&2&-3&-3\end{array}\right][/tex]
Now for the row operations:
• swap rows 1 and 2
[tex]\left[\begin{array}{cccc|c}1&2&-3&1&12\\2&-1&2&1&-3\\3&-1&-1&2&3\\-2&3&2&-3&-3\end{array}\right][/tex]
• add -2 (row 1) to row 2, -3 (row 1) to row 3, and 2 (row 1) to row 4
[tex]\left[\begin{array}{cccc|c}1&2&-3&1&12\\0&-5&8&-1&-27\\0&-7&8&-1&-33\\0&7&-4&-1&21\end{array}\right][/tex]
• add 7 (row 2) to -5 (row 3), and row 3 to row 4
[tex]\left[\begin{array}{cccc|c}1&2&-3&1&12\\0&-5&8&-1&-27\\0&0&16&-2&-24\\0&0&4&-2&-12\end{array}\right][/tex]
• multiply through rows 3 and 4 by 1/2
[tex]\left[\begin{array}{cccc|c}1&2&-3&1&12\\0&-5&8&-1&-27\\0&0&8&-1&-12\\0&0&2&-1&-6\end{array}\right][/tex]
• add -4 (row 4) to row 3
[tex]\left[\begin{array}{cccc|c}1&2&-3&1&12\\0&-5&8&-1&-27\\0&0&0&3&12\\0&0&2&-1&-6\end{array}\right][/tex]
• swap rows 3 and 4
[tex]\left[\begin{array}{cccc|c}1&2&-3&1&12\\0&-5&8&-1&-27\\0&0&2&-1&-6\\0&0&0&3&12\end{array}\right][/tex]
• multiply through row 4 by 1/3
[tex]\left[\begin{array}{cccc|c}1&2&-3&1&12\\0&-5&8&-1&-27\\0&0&2&-1&-6\\0&0&0&1&4\end{array}\right][/tex]
• add row 4 to row 3
[tex]\left[\begin{array}{cccc|c}1&2&-3&1&12\\0&-5&8&-1&-27\\0&0&2&0&-2\\0&0&0&1&4\end{array}\right][/tex]
• multiply through row 3 by 1/2
[tex]\left[\begin{array}{cccc|c}1&2&-3&1&12\\0&-5&8&-1&-27\\0&0&1&0&-1\\0&0&0&1&4\end{array}\right][/tex]
• add -8 (row 3) and row 4 to row 2
[tex]\left[\begin{array}{cccc|c}1&2&-3&1&12\\0&-5&0&0&-15\\0&0&1&0&-1\\0&0&0&1&4\end{array}\right][/tex]
• multiply through row 2 by -1/5
[tex]\left[\begin{array}{cccc|c}1&2&-3&1&12\\0&1&0&0&3\\0&0&1&0&-1\\0&0&0&1&4\end{array}\right][/tex]
• add -2 (row 2) and 3 (row 3) and -1 (row 4) to row 1
[tex]\left[\begin{array}{cccc|c}1&0&0&0&-1\\0&1&0&0&3\\0&0&1&0&-1\\0&0&0&1&4\end{array}\right][/tex]
Then the solution to the system is (x, y, z, w) = (-1, 3, -1, 4).
Find the factors of function f, and use them to complete this statement. f(x)=2x^(4)-x^(3)-18x^(2)+9x
From left to right, function f has zeros at
Hello,
[tex]f(x)=2x^4-x^3-18x+9x\\\\=x(2x^3-x^2-18x+9)\\\\=x(x^2(2x-1)-9(2x-1))\\\\=x(2x-1)(x^2-9)\\=x(2x-1)(x-3)(x+3)\\[/tex]
Zeros are : 0; 1/2; -3; 3.
The zeros of the function are -3, 0, 1/2 and 3.
The given function is [tex]f(x)=2x^{4} -x^{3} -18x^{2} +9x[/tex].
What are the zeros of a function?Zeros of a function are the points where the graph of the function meets the X-axis i.e., at the solutions of f(x) = 0.
Now, factorise the given function, that is f(x)=x(2x³-x²-18x+9).
=x[x²(2x-1)-9x(2x-1)]
=x(2x-1)(x²-9)
=x(2x-1)(x+3)(x-3)
= -3, 0, 1/2, 3
Therefore, the zeros of the function are -3, 0, 1/2 and 3.
To learn more about the zeros of the function visit:
https://brainly.com/question/16633170.
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Giving a test to a group of students, the grades and gender are summarized below
A B C Total
Male 20 10 13 43
Female 15 2 11 28
Total 35 12 24 71
If one student is chosen at random,
Find the probability that the student did NOT get an "B"
Answer:
59 / 71
Step-by-step explanation:
Given the data :
A B C Total
Male 20 10 13 43
Female 15 2 11 28
Total 35 12 24 71
The probability of randomly selecting a Student that got B ;
Probability = required outcome / Total possible outcomes
P(getting B) = number of students who got B / total number of students
P(getting B) = 12 / 71
Probability of getting B = 12 /71
Probability of not getting B = P(getting B)' = 1 - P(getting B)
Probability that student did not get "B" = 1 - 12/71 = 59 / 71
HELP PLEASE- ASAP
What is the probability that a point selected randomly in will be one of the points inside segment RS? Enter your answer as a decimal numbers
Answer:
0.2
Step-by-step explanation:
The total number of points in PS is a sum of the number of points in :
PQ + QR + RS ;
PQ = 7 ; QR = 13 ; RS = 5
PS = (7 + 13 + 5) = 25
Probability that point selected at random is in RS ;
Required outcome = point in RS
Total possible outcomes = points in PS
Probability = RS / PS = 5 / 25 = 0.2
What is the solution set of the equation x2+3*-4=6
Answer:
x=9
Step-by-step explanation:
Annual entertainment expenses in a population of 100 families have a mean of $2040 and a standard deviation of $360.
(a) Find the mean and standard deviation of monthly expenses.
(b) What is the total amount of monthly entertainment expenses for this population?
Answer:
The correct answer is:
(a) Mean = 170,
Standard deviation = 30
(b) 1700
Step-by-step explanation:
Given:
n = 100μ = 2040σ = 360(a)
Mean of monthly expenses will be:
= [tex]\frac{\mu}{2}[/tex]
= [tex]\frac{2040}{2}[/tex]
= [tex]170[/tex]
Standard deviation will be:
= [tex]\frac{\sigma}{12}[/tex]
= [tex]\frac{360}{12}[/tex]
= [tex]30[/tex]
(b)
The total amount of monthly expenses will be:
= [tex]n\times \frac{\mu}{12}[/tex]
= [tex]100\times 170[/tex]
= [tex]1700[/tex]
Solve the equation for x.
2/3x-1/9x+5=20
Answer:
x = 27
Step-by-step explanation:
I'm assuming the equation looks like this:
[tex]\frac{2}{3}x-\frac{1}{9}x+5=20[/tex]
Here's how to solve for x:
[tex]\frac{2}{3}x-\frac{1}{9}x+5=20[/tex]
(subtract 5 from both sides)
[tex]\frac{2}{3}x-\frac{1}{9}x=15[/tex]
(Find the GCF of 3 and 9, which is 3. Multiply 2/3 by 3/3. You get 6/9)
[tex]\frac{6}{9}x-\frac{1}{9}x=15[/tex]
(add like terms)
[tex]\frac{5}{9}x=15[/tex]
(multiply 9/5 to both sides, which is the same as dividing both sides by 5/9)
x = 27
Hope it helps (●'◡'●)
Assume one individual from the group is randomly selected. Find the probability of getting someone who tests negative, given that he or she had the disease. the probability is approximately?
Answer:
[tex]P(Negative | Yes) = 0.0486[/tex]
Step-by-step explanation:
Given
[tex]\begin{array}{ccc}{} & {Yes} & {No} & {Positive} & {137} & {24} & {Negative} & {7} & {132} \ \end{array}[/tex]
Required
[tex]P(Negative | Yes)[/tex]
This is calculated as:
[tex]P(Negative | Yes) = \frac{n(Negative\ n\ Yes)}{n(Yes)}[/tex]
So, we have:
[tex]P(Negative | Yes) = \frac{7}{137+7}[/tex]
[tex]P(Negative | Yes) = \frac{7}{144}[/tex]
[tex]P(Negative | Yes) = 0.0486[/tex]
Which method correctly solves the equation using the distributive property?
Negative 0.2 (x minus 4) = negative 1.7
Negative 0.2 (x minus 4) = negative 1.7. Negative 0.2 x minus 4 = negative 1.7. Negative 0.2 x = 2.3. x = negative 11.5.
Negative 0.2 (x minus 4) = negative 1.7. x minus 4 = 0.34. x = 4.34.
Negative 0.2 (x minus 4) = negative 1.7. Negative 0.2 x + 0.8 = negative 1.7. Negative 0.2 x = negative 2.5. x = 12.5.
Negative 0.2 (x minus 4) = negative 1.7. Negative 0.2 x minus 0.8 = negative 1.7. Negative 0.2 x = negative 0.9. x = 4.5.
9514 1404 393
Answer:
(c) x = 12.5
Step-by-step explanation:
-0.2(x -4) = -1.7
-0.2x +0.8 = -1.7 . . . eliminate parentheses using the distributive property
-0.2x = -2.5 . . . . . . subtract 0.8
x = 12.5 . . . . . . . . divide by -0.2
Find the range of the data set represented by this box plot.
25
70
20
60
Answer:
D. 60
Step-by-step explanation:
Range is the difference between the maximum value and the minimum value.
The minimum value is at the extreme end of the whisker of the box plot to your left = 65
The maximum value is at the extreme end of the whisker of the box plot to your right = 125
Range = 125 - 65 = 60
The graph shows the solution of the following system of equations. y = –5∕3x + 3 y = 1∕3x – 3
Answer:
So whats your question ??
Step-by-step explanation:
What is the surface area of the rectangular prism pictured below?
3 meters
9 meters
4 meters
Answer:
108 meters with the formula lxhxw
Assume 10% of Berkeley students are left-handed. If you are in a class of 50 people, what is the probability that exactly 4 of them are left-handed? Round your answer to the nearest hundredth, and omit the leading zero. Enter your answer here.
Answer:
The answer is "0.18"
Step-by-step explanation:
[tex]10\% \ of \ 50= 5 \text{are left handed}\\\\45\ \text{are right handed}\\\\[/tex]
If the probability exactly 4 were heft handed
[tex]=^{50}_{C_4}\times (\frac{5}{50})^4 \times (\frac{45}{50})^{4b}\\\\=^{50}_{C_4} \times (0.1)^4 \times (0.9)^{4b}\\\\=230300 \times (0.1)^4 \times (0.9)^{4b}\\\\=0.181 \approx 0.18[/tex]
Help asap! Lia can rent a van for either $90 per day with unlimited mileage or $50 per day with 250 free miles and an extra 25¢ for each mile over 250. For what number of miles traveled in one day would the unlimited mileage plan save Lia money? (Show work)
Answer:
The unlimited mileage plan would save money for Lia from 410 miles onwards.
Step-by-step explanation:
Since Lia can rent a van for either $ 90 per day with unlimited mileage or $ 50 per day with 250 free miles and an extra 25 ¢ for each mile over 250, to determine for what number of miles traveled in one day would the unlimited mileage plan save Lia money, the following calculation must be performed:
90.25 - 50 = 40.25
40.25 / 0.25 = 161
161 + 250 = 411
Therefore, the unlimited mileage plan would save money for Lia from 410 miles onwards.
HELPPPP ME ASAP
If f(x) = x2, g(x) = 5x, and h(x) = x +4, find each value.
Find g[h(-2)]
9514 1404 393
Answer:
10
Step-by-step explanation:
Put the values where the arguments are and do the arithmetic.
g(h(-2)) = g(-2+4) = g(2) = 5(2)
g(h(-2)) = 10
log2(6x) – log2 (x)-2
Answer:
xlog(64)−xlog(2)−2
Step-by-step explanation:
Simplify 6log(2) by moving 6 inside the logarithm.
log(2^6)x − log(2)x − 2
Raise 2 to the power of 6.
log(64)x − log(2)x − 2
Reorder factors in log(64)x − log(2)x −2.
evaluate expression when a=5 b= -3
6a-b
Find the appropriate answer for each word problem.
a. A group of twelve art students are visiting a local art museum for a field trip. The total cost of admission for the students is $125. What is the cost of admission for each student?
b. The school van can carry twelve passengers at a time. What is the least number of trips the van must make in order to bring 125 passengers to the same location?
c. Charlotte and her mother baked 125 cookies to give as Christmas gifts to their neighbors. If they plan to give a dozen cookies to each neighbor, how many neighbors will receive a gift?
d. Nicholas and Elaine are planning to serve cheesecake for dessert at their wedding and have purchased twelve cheesecakes. If the cheesecakes are divided evenly among the 125 wedding guests, how much cheesecake will each guest receive?
I WILL GIVE BRAINLIEST IF CORRECT
Answer:
a. $10
b. 10.46
c. 10.46
d. 0.096
Assume the random variable X is normally distributed, with mean of 50 and a standard deviation of 9. Find the 9th percentile.
Answer:
37.94
Step-by-step explanation:
the 9th percentile is equal to a zscore of -1.34
-1.34=(x-50)/9
x=37.94
1. Write 3.3.3.3.3 as a power.
Answer:
3^5
Step-by-step explanation:
On the iPad it looks like that but the five is on the top right smaller
Answer:
3⁵
every 3 has it own power that is 1 however that .3 confused us
10=−4x+3x^2 solve
please help!
Answer:
-1.28 AND 2.61
Step-by-step explanation:
[tex]10= -4x+3x^2\\ 3x^2 -4x - 10 = 0\\\\[/tex]
use quadratic formula
x = [tex]\frac{-b+\sqrt{b^{2} -4ac} }{2a}[/tex] x = [tex]\frac{-b-\sqrt{b^{2} -4ac} }{2a}[/tex]
Solution/X-Intercepts: -1.28 AND 2.61
Estimate 19.625-6.77 by first rounding each number to the nearest tenth.
Answer:
13
Step-by-step explanation:
1. Round 19.625 up to 20.
2. Round 6.77 up to 7.
3. Calculate the equation. Ans is 13.
